EP4003253A1

EP4003253A1 - Wound cleaning product

Info

Publication number: EP4003253A1
Application number: EP20740573.9A
Authority: EP
Inventors: Marc Pehr; Birthe LANG; Bernd Schlesselmann
Original assignee: Carl Freudenberg KG
Current assignee: Carl Freudenberg KG
Priority date: 2019-07-31
Filing date: 2020-07-10
Publication date: 2022-06-01
Also published as: US20220203650A1; DE102019120712A1; CN114144304A; WO2021018544A1

Abstract

The invention relates to a wound cleaning product, comprising a composite material (1) having a foam layer (2) and a fiber layer (3) disposed on and in the foam layer (2). The fiber layer (3) is at least partially thermally solidified and the foam layer (2) and the fiber layer (3) are interlinked by needlepunching, fibers of the fiber layer (3) having penetrated the foam layer (2) and forming capillary channels (4) that extend from the fiber layer (3) into the foam layer (2).

Description

Wound cleansing articles

description

The invention relates to a wound cleansing article comprising a

Composite material which has a foam layer and a fiber layer arranged on and in the foam layer and a method for its production.

Wound cleaning (debridement) plays a role in wound treatment, i.e. cleaning the wound of necrotic (dead), infected or damaged tissue, fibrin coverings, wound exudate and others

Pollution plays an integral role. Necrotic tissue and / or a strong presence of bacteria can seriously hinder the healing process of a wound. It is therefore medically advisable to perform debridement between every dressing change, especially in the case of chronic wounds. There are several methods that are used to cleanse wounds. In all methods, it is essential that when the dead tissue is removed, newly formed granulation and young epithelial tissue, which form when the wound closes, are not damaged.

One method that is increasingly used is the mechanical one

Wound cleansing. Various flat structures, for example textiles or sponges, are used to clean the wound. An advantage of the mechanical wound cleaning is that it is easy to perform and can also be used in home care by caregivers.

The requirements for flat structures for mechanical wound cleaning are diverse. On the one hand, they must have an abrasive character that is tailored to the application and that can be removed gently and painlessly

allows necrotic tissue and coverings, on the other hand, have a good absorption capacity, which enables a quick absorption of the loosened wound coverings and thus prevents renewed contamination of the wound. In addition, the flat structure should also be suitable for cleaning the surrounding skin, for which a less abrasive surface is suitable. Furthermore, the structure should be flexible, allowing cleaning

A wide variety of wound geometries is possible, i.e. both large-area wounds and tunnels.

The use of different fabrics for mechanical

Wound cleansing is already known.

WO 2019/028057 A1 describes a hydrophilic foam with a moisture content between 20% by weight and 60% by weight with a structure that allows the wound to be debridement. The disadvantage here is that the abrasiveness is determined by the moisture content. In practice, this is not practical, since it is very time-consuming for the nursing staff to use the wound irrigation solution in a dosed manner. Another disadvantage is that there are no surfaces with

different abrasives are available for cleaning.

In WO 2019/057256 A1, two foam layers laminated to one another are presented. On one side there is a foam side with indentations and notches. Various structures and surfaces are provided for cleaning. The disadvantage of this system is that the Lamination of the two foams can lead to increased rigidity.

Furthermore, a different swelling behavior of the foams harbors the risk of delamination of the layers.

A commercially available foam for mechanical debridement is the Wundputzer® from Ligasano®. The reticulated hydrophobic foam shows good cleaning performance due to its highly abrasive structure. This

However, structure can also lead to severe pain for the patient during use. The reticulated foam has high open pores in order to remove solid and highly viscous wound components. However, this leads to a reduced absorption capacity.

In addition to foams, the use of flat textile structures for cleaning wounds is also described.

EP 2 365 794 B1 describes a wound cleaning device which has or is a cloth which has a carrier layer with threads made of synthetic fibers that protrude or are arranged thereon

preferably have cut ends or end faces. The disadvantage is that the cleaning effect is achieved by the protruding fibers. This quickly leads to the fiber ends sticking together, particularly in the case of wounds with viscous exudate, which results in a rapid exhaustion of the capacity of the cloth. In addition, the between the fibers

provided flea spaces are not so well suited for receiving and enclosing the wound components due to their elongated geometry.

A commercially available product of the aforementioned structure is the wound cleansing product Debrisoft®. In addition to the above

The disadvantage is that the product has hard, trimmed edges, which can cause severe pain on contact with the wound base. However, the edges are necessary to hold the textile structure together, since fibers are released when the product is cut, which can contaminate the wound. In addition, it has a high level of rigidity so that it is only suitable for use on flat wounds. Furthermore, exudate is only bound to the surface and not absorbed into the structure of the cloth. After all, it can only be used on one side.

EP 2777662 B1 describes a velor nonwoven for use in wound cleaning, characterized in that the fibers are in loops. Flieran's advantage is that the loop structure allows necroses and wound secretions to be easily removed and taken up in the structure. The disadvantage of the described invention is that abrasion and absorption are carried out from the same layer and as a result cannot be varied as desired independently of one another.

US 20030079324 A1 describes a method for producing a structured, permeable nonwoven fabric solidified by means of a water jet, with high absorption capacity and good abrasion, in particular in the moist state. The disadvantage here is the small thickness of the material due to the manufacturing process, which means that there is only little space available for receiving and enclosing the wound components.

US 20170304485 A1 describes a particle-containing porous nonwoven fabric matrix, consisting of polyolefins and glass fibers, which contains a large number of particles that bind to microorganisms. The disadvantage of using glass fibers is that they have a very high level of abrasiveness, which can be very uncomfortable for the patient. Furthermore, there are no different surfaces with different surface properties available. A commercially available and widely used fiber-based mechanical wound cleansing product is cotton gauze. This is an open fabric made of cotton yarns and is characterized on the one hand by its low price and on the other hand by its high versatility. A disadvantage of this product is that it can be painful for the patient to use due to the coarse yarn structure. In addition, there is a risk of contamination of the wound by fiber components loosening from the yarn, especially when the gauze is cut to size.

WO 2013/113906 A1 describes a wound care article having at least one surface with abrasive properties, which is designed so that the wound care article is suitable for breaking up biofilms arranged in the wound and / or for stimulating wound exudation when it moves relative to a wound. The surface with abrasive properties can be a foam or fibers. A product is also described which contains both a polyurethane foam and a textile material laminated to it. The disadvantage of this composite material is its high level

Stiffness and tendency to delaminate. In addition, the transport of wound exudate through the structure is made more difficult by the lamination.

A commercially available product of the above structure is that

Cutimed® DebriClean wound cleansing product. In addition to the

disadvantages mentioned above, the product has the disadvantage that it has hard edges and high rigidity, which makes it only suitable for

large wounds are suitable. Furthermore, it can only be used on one side.

The invention is based on the object of providing a wound cleansing article with which the aforementioned disadvantages can be at least partially eliminated. In particular, the wound cleaning article should enable good and gentle wound cleaning. It should be necrotic Tissue and coverings can be removed without applying excessive force, so that the risk of injuring young granulation tissue is minimized.

In addition, it should have at least two areas of different abrasiveness so that they can be optimized independently of one another for cleaning the wound and the surrounding skin. As a result, both the wound and the surrounding skin can be optimally treated with one article. In addition, the article should be able to be used for different wound geometries, for example large-area or tunnel-shaped wounds. Furthermore, the article should be capable of being cut and used without significant loss of fibers.

This object is achieved by a wound cleansing article comprising a composite material that has a foam layer and a fiber layer arranged on and in the foam layer, the fiber layer being at least partially thermally solidified and the foam layer and fiber layer being connected to one another by needling, with fibers of the fiber layer have penetrated into the foam layer and form capillary channels that extend from the fiber layer into the foam.

The wound cleansing article according to the invention is characterized in that it has a foam layer and a fiber layer which are connected to one another by needling. Through this mechanical connection, fibers of the fiber layer penetrate the foam layer and form capillary channels. According to the invention, capillary channels are understood to mean the elongated cavities formed between the fibers aligned by needling. The capillary channels extend from the fiber layer into the foam layer and thus enable a good and fast

Cross-layer transport of exudate as well as its inclusion in the entire wound cleansing article. The needling of the fiber layer and foam layer creates a structure with high tensile strength. The composite material can have a maximum tensile force / elongation measured according to EN 29073-03 (wet) of more than 40%,

for example from 40% to 180%, preferably more than 50%,

for example from 50% to 180%, more preferably more than 60%, for example from 60% to 180%, even more preferably more than 70%,

for example from 70% to 180%, more preferably more than 80%, for example from 80% to 180%, even more preferably more than 90%, for example from 90% to 180%, and in particular more than 100%, for example from 100% to 180%. Furthermore, a two-sided material can be obtained both with swelling and with

associated expansion of the layers, there is no risk of delamination.

Furthermore, it was surprisingly found that the needling of the fiber layer and the foam layer would enable a liquid transport between the layers, which enables a quick removal of wound exudate and a secure containment inside the structure. In a preferred embodiment, the fibers of the fiber layer penetrate the foam layer and at least partially protrude from the side of the foam layer facing away from the fiber layer. This is advantageous because it makes a special

pleasant feel of the foam side can be achieved. In addition, the outstanding fiber ends can be characterized by their high specific

Surface to further increase the cleaning effect of the foam layer.

For some applications, the fiber layer is used as a

The cleaning side is advantageous compared to the foam layer, since fibers are generally less abrasive than foams, so that gentle cleaning of the surrounding skin is possible. In addition, the fibers offer a higher specific surface area than the foam for cleaning and adsorption of small dissolved wound components and bacteria. It was also found that the wound cleaning article according to the invention enables gentle wound cleaning. In particular, the detachment of viscous and encrusted components is possible even at low pressure. Of

The wound cleansing article according to the invention also enables

different surface structures in a single material, so that different cleaning needs can be addressed with a single product.

According to the invention, the fiber layer is thermally consolidated. The fibers can be fixed well through the thermal consolidation, so that the risk of fiber loss and thus contamination of the wound can be reduced. In addition, the degree of thermal solidification can

Abrasiveness can be adjusted in a targeted manner.

The thermal consolidation preferably takes place in that the fiber layer is thermally consolidated before it is applied to the foam layer. As a result, the foam layer can be prevented from being adversely affected by the heating.

Practical experiments have shown that it is particularly useful if the fiber layer is a fiber layer that has been thermally consolidated without compression. This has the advantage that a large proportion of the pore volume is available to absorb wound components even after solidification. Furthermore, a fiber layer with a rough surface can be obtained in this way, which enables the loosening of hard-to-dissolve coatings in the wound. In addition, this allows the flexibility of the fiber layer to be retained. A thermal solidification without compression can

take place, for example, by treating the fiber layer with hot air, for example in a through-air oven. It is further preferred if the fiber layer is a flat, thermally solidified fiber layer. This is not thermally solidified over a large area

Fiber layers, such as point-calendered fiber layers, are advantageous as this prevents individual fibers from becoming detached from the fiber layer and contaminating the wound.

In a preferred embodiment of the invention, the fiber layer is a nonwoven fabric, in particular a nonwoven fabric according to DIN EN ISO 9092: 2019-08, a woven fabric, a knitted fabric and / or a knitted fabric, the aforementioned

Fiber layers are each at least partially thermally solidified. The fiber layer is particularly preferably an at least partially thermally bonded nonwoven material, since this allows the fibers to penetrate the foam layer particularly well due to its open structure.

The fiber layer can have a wide variety of fibers. Synthetic fibers are preferred because they are easy to sterilize. More preferred are hydrophobic fibers, ie fibers which are made at least on their surface from polymers whose surface energy is less than 50 mJ / m ² . Particularly suitable hydrophobic fibers are polyester and / or polyolefin fibers. The advantage of hydrophobic fibers is that they enable bacteria to be attached and thus removed. The binding of bacteria to hydrophobic fibers is described, for example, in N. Edwards et al. Role of surface energy and nanoroughness in the removal efficiency of bacterial contamination by nonwoven wipes from frequently touched surfaces, Science and Technology of advanced materials, 2017, Vol. 18, No. 1 197-209.

To form the framework structure, the fiber layer preferably has

Matrix fibers. According to the invention, matrix fibers are to be understood as meaning fibers which are not, or only to a small extent, thermally fused. Preferred are thermoplastic matrix fibers that have a

Melting point of the lowest melting fiber component of over 170 ° C, for example from 170 ° C to 250 ° C, more preferably above 200 ° C. In one embodiment, the matrix fibers consist of a fiber component. In a further preferred embodiment, the matrix fibers consist of several fiber components. Solid profile fibers, multilobal solid profile fibers, flea fibers and / or are particularly preferred

Full profile bicomponent fibers (e.g. core / sheath, side-by-side). If the fiber layer has binding fibers, it is advantageous if the melting point of the fiber component contained in the matrix fiber is the lowest

Melting point is above the melting point of the fiber component contained in the binder fiber with the highest melting point. The melting point of the fiber component with the lowest melting point in the matrix fiber is preferably at least 10 ° C., particularly preferably at least 30 ° C., above the melting point of the fiber component with the highest

Melting point in the binding fiber. Suitable polymer classes for forming the matrix fibers can include polyesters, polyamides, polyolefins,

Be polyacrylonitrile, cellulose and / or polyvinyl alcohols.

Particularly suitable matrix fibers are hydrophobic matrix fibers.

The proportion of matrix fibers in the fiber layer is preferably at least 20% by weight, for example from 20% by weight to 90% by weight and / or from 20% by weight to 80% by weight, and / or from 20% by weight Wt .-% to 70 wt .-%, more preferably at least 25 wt .-%, for example from 25 wt .-% to 80 wt .-% and / or from 25 wt .-% to 70 wt .-%, still more preferably at least 30% by weight, for example from 30% by weight to 70% by weight, in each case based on the total weight of the fiber layer.

In a preferred embodiment, the fiber layer has a binding agent, for example thermoplastic binding agents and / or binding fibers. Binding fibers are fibers that are at least partially fused and thereby Create binding points between the fibers. This enables thermal consolidation and targeted adjustment of the abrasiveness of the fiber layer. The binding fiber preferably has at least one fusible fiber component, in particular a fusible component arranged on the outside

Fiber component, has a melting point that is lower than that

Melting point of other fiber components contained in the fiber layer, in particular lower than the melting point of the lowest-melting fiber component of the matrix fibers.

If the binding fiber has several fusible fiber components, the melting point of the highest melting fiber component is the

Binder fiber preferably more than 10 ° C., particularly preferably more than 30 ° C. below the melting point of the lowest melting fiber component of the matrix fibers. Suitable binding fibers have a melting point of the highest melting fiber component of below 250 ° C, for example from 100 ° C to 200 ° C, more preferably below 180 ° C, for example from 100 ° C to 180 ° C, in particular below 175 ° C, for example from 100 ° C to 175 ° C.

Preferred fusible components in binding fibers are polyolefin,

Polyester, polyamide and / or mixtures thereof and copolymers such as

Ethylene vinyl acetate copolymers. Likewise preferred binding fibers are bicomponent fibers, in particular bicomponent fibers which contain polyolefin, polyester, ethylene-vinyl acetate copolymers, polybutylene terephthalate, and / or mixtures thereof as externally arranged fiber components. The binding fibers can have different cross-sectional geometries such as

Full profile fiber, multilobal full profile fiber, hollow fiber,

Have full profile bicomponent fiber (e.g. core / sheath, side-by-side) geometries. Fusible bonding fibers in the form of full-profile fibers are preferred. Particularly suitable binders are hydrophobic binder fibers, in particular polyester and / or polyolefin fibers.

The proportion of binding fibers in the fiber layer is preferably at least 10% by weight, for example from 10% by weight to 80% by weight and / or from 10%

% By weight to 70% by weight, and / or from 10% by weight to 60% by weight, more preferably at least 25% by weight, for example from 25% by weight to 80% by weight and / or from 25% by weight to 70% by weight, and / or from 25% by weight to 60% by weight, more preferably at least 30% by weight, for example from 30% by weight to 80% by weight % and / or from 30% by weight to 70% by weight, and / or from 30% by weight to 60% by weight, in each case based on the total weight of the fiber layer.

Thermoplastic binders can be co-polyamide, co-polyester, polyolefins, polyvinyl alcohol (PVA), ethylene vinyl acetate (EVA), thermoplastic

Polyurethane (TPU), polycaprolactone, terpolymers and / or mixtures thereof. The thermoplastic binder preferably contains the abovementioned polymers in an amount of more than 50% by weight, particularly preferably more than 70% by weight, in particular more than 90% by weight, based in each case on the total weight of the binder. Preferred thermoplastic binders have a melting point of 90 ° C to 200 ° C. Particularly suitable

Thermoplastic binders are hydrophobic, i.e. made from polymers with a surface energy of less than 50 mJ / m2.

In a preferred embodiment, the fibers contained in the fiber layer, in particular the matrix fibers and / or the binding fibers, are still staple fibers, preferably with a staple length between 20 mm and 150 mm

more preferably between 30 mm and 90 mm and in particular between 40 mm and 70 mm. The fiber titer of the fibers contained in the fiber layer, in particular the matrix fibers and / or binding fibers, is preferably in the range from 0.9 dtex to 100 dtex (g / 10,000 m). The fiber titer is even more preferably between 1.5 dtex and 30 dtex, in particular between 3 dtex and 11 dtex.

The fiber layer preferably has an average thickness, determined microscopically, of at least 1.5 mm, for example from 1.5 mm to 10 mm, even more preferably of at least 2 mm, for example from 2 mm to 10 mm, and / or from 4 mm to 10 mm and / or from 2 mm to 5 mm and / or from 5 mm to 8 mm.

The weight per unit area of the fiber layer is preferably 50 g / m ² to 400 g / m ² , more preferably 50 g / m ² to 350 g / m ² , even more preferably 50 g / m ² to 300 g / m ² , even more preferably 50 g / m ² to 250 g / m ² , in particular 50 g / m ² to 200 g / m ² .

According to the invention, the most varied foams, in particular polymer foams, can be used as the foam layer. The foam layer is preferably based on polyurethane foam, for example polyether polyurethane or polyester polyurethane foam, polyetherester polyurethane foam,

Polyvinyl acetate foam, polyvinyl alcohol foam or mixtures of these foams. The term “based on” means more than 50% by weight, more preferably more than 70% by weight, in particular more than 90% by weight, based on the polymer content of the foam layer.

The foam layer particularly preferably contains a hydrophilic one

Polymer foam, i.e. a foam with an absorption capacity of at least 4 g / g, for example from 4 g / g to 50 g / g, preferably from 4 g / g to 30 g / g and more preferably from 4 g / g to 25 g / g in a proportion of more than 50% by weight, more preferably more than 70% by weight, in particular more than 90% by weight, based on the polymer content of the foam layer. A polymer foam made from hydrophilic polymers is also preferred hydrophilic polyurethanes, in particular hydrophilic polyurethanes as described in WO2018 / 007093, is manufactured. A hydrophilic polymer foam allows viscous wound components to be absorbed quickly. Furthermore, it enables the necroses to be soaked if it is soaked beforehand with wound irrigation solution and applied to the wound. A polyurethane foam is very particularly preferred since it combines high hydrophilicity with good elasticity and retention. The advantage of good retention is the secure inclusion of removed wound components, so that recontamination of the wound or the wound environment can be prevented.

In a particularly preferred embodiment of the invention, the

Open-lined foam layer. According to the invention, the term “open-line” is to be understood as meaning that the majority of the pores are connected to one another by pore openings. The advantage of this is that absorbed wound components can be absorbed well in the structure and distributed homogeneously.

In a further preferred embodiment, the foam layer has at least one open-line surface. According to the invention, the term “open-line surface” is to be understood as meaning that the percentage of the area of open pores in relation to the total surface of the foam would be

at least 50%, for example 50% to 98%, even more preferably at least 60%, for example 60% to 98%, in particular at least 70%, for example 70% to 98%. Advantageous in such a

open-line foam is that it has a slightly abrasive character, which allows a gentle loosening of deposits and at the same time loosened

Can hold back wound components well in the structure, so that a

Contamination of the wound is prevented.

In a further embodiment, the foam layer has a reticulated foam. In reticulated foams, the open-cell structure is enhanced by the Tear open the pore walls by means of a gas explosion in the foam pores.

The basis weight of the foam layers is preferably 50 g / m ² to 600 g / m ² _, more preferably 80 g / m ² to 500 g / m ² , even more preferably 100 g / m ² to 400 g / m ² , even more preferably 120 g / m ² to 350 g / m ² , in particular 120 g / m ² to 250 g / m ² .

The mean thickness of the foam layer is preferably 1 mm to 15 mm, particularly preferably 2 mm to 10 mm and particularly preferably 3 mm to 8 mm.

The mean pore size of the foam would be at least 0.2 mm, for example 0.2 mm to 3 mm, more preferably at least 0.25 mm, for example 0.25 mm to 2.5 mm, in particular at least 0.3 mm, for example 0 , 3mm to 2.2mm.

In a further preferred embodiment of the invention, the average density of the foam layer is at least 50 kg / m ³ , preferably from 70 kg / m ³ to 150 kg / m ³ and in particular from 90 kg / m ³ to 150 kg / m ³ .

In a preferred embodiment, the composite material has a

Absorbent capacity of at least 4 g / g, for example from 4 g / g to 50 g / g, preferably from 4 g / g to 30 g / g and more preferably from 6 g / g to 25 g / g.

The basis weight of the composite material is preferably 100 g / m ² to 1000 g / m ² , more preferably 200 g / m ² to 900 g / m ² , even more preferably 200 g / m ² to 600 g / m ² , even more preferably 200 g / m ² to 500 g / m ² , in particular 250 g / m ² to 450 g / m ² . In a preferred embodiment of the invention, the composite material has a hydrophilic foam layer in combination with a hydrophobic one

Fiber layer. A hydrophilic foam layer is a foam layer with an absorption capacity of at least 4 g / g, for example from 4 g / g to 50 g / g, preferably from 4 g / g to 30 g / g and even more preferably from 4 g / g to 25 g / g understood. Likewise preferred is a foam layer which consists of a polymer foam which has hydrophilic polymers, preferably hydrophilic ones

Polyurethanes, especially hydrophilic polyurethanes as in the

WO2018 / 007093 described, contains, preferably in a proportion of at least 50% by weight, more preferably at least 70% by weight,

in particular at least 90% by weight based on the total weight of the foam layer.

In a particularly preferred embodiment, the composite material has a hydrophilic foam layer in combination with a hydrophobic one

Fiber layer, wherein hydrophobic fibers of the fiber layer penetrate the hydrophilic foam layer and at least partially protrude from the side of the foam layer facing away from the fiber layer. The advantage of this embodiment is that a bifunctional surface is provided on the foam layer which, due to the hydrophilic character of the foam layer, enables the rapid absorption of viscous wound components and, at the same time, due to the comparatively high specific surface of the protruding fibers, the adsorption of bacteria and other hydrophobic ones Components enables.

A hydrophobic fiber layer is understood to mean a fiber layer that contains hydrophobic fibers, ie fibers made from polymers whose surface energy is less than 50 mJ / m ² , preferably in a proportion of at least 50% by weight, more preferably at least 70 % By weight, in particular at least 90% by weight, based on the total weight of the fiber layer. Particularly suitable hydrophobic fibers are polyester and / or polyolefin fibers.

The wound cleaning article is preferably sterile for use in cleaning wounds.

Another object of the present invention relates to the positioning of a wound cleansing article according to the invention comprising the following

Steps:

A arranging an at least partially thermally consolidated fiber layer on a foam layer;

B Needling the foam layer and fiber layer in such a way that a

Composite material forms in which the fibers of the fiber layer in the

Foam layer have penetrated and form capillary channels that extend from the fiber layer into the foam.

Another subject matter of the present invention relates to an alternative positioning of a wound cleansing article according to the invention, comprising the following steps:

A placing a fiber layer on a foam layer;

B Needling of foam and fiber layers in such a way that a

Composite material forms in which the fibers of the fiber layer in the

C Thermal consolidation of the composite material. Measurement methods:

Determination of open-cell surface: The open-cell content of the surface is determined by recording a light microscopic image (interference microscope light source green) of the surface of the foam layer over an area of 1 cm × 1 cm and by subsequent optical evaluation. The percentage of the area of open pores in relation to the total surface of the foam layer is determined.

Pore diameter of the pores in the foam layer: The pore diameter is determined by optical evaluation of light microscopy images by creating an outer circle. The pore diameter corresponds to that

Diameter of the outer circle. The evaluation of at least 10 pores is averaged.

Absorbance Capacity: A test solution as described in BS EN 13726-1: 2002 is used for absorbance measurements. A 100 cm ² sample is first weighed (W1), then placed in the test solution and left there for at least ten minutes. The sample is then carefully gripped at one corner without squeezing the sample and allowed to drain for two minutes. The weight is then determined again (W2). The

Absorption capacity is now calculated by dividing the difference in amount between W2 and W1 by the initial weight W1 as absorption [g] per [g] density of the foam layer: The density is determined by taking a sample

cut out, weighed and the thickness is determined. The volume is then calculated by multiplying the thickness by the area of the sample and finally dividing the weight by the volume.

Thickness of the foam layer: The thickness of the foam layer is determined microscopically before needling with the fiber layer. Description of the figures Brief description of the drawing The drawings show:

1 shows the cross section of a CT image of a composite material according to the invention,

2 shows the cross section of a light microscope image of a

composite material according to the invention after a wound cleaning,

3 shows the cross section of a scanning electron microscope image of a cotton gauze after cleaning the wound,

4 shows the cross section of a scanning electron microscope image of a wound cleansing material according to the invention after a wound cleansing,

5 shows the defined movement of a wiping cycle for cleaning a test wound on pig skin,

6 shows the cross section of a scanning electron microscope image of the Debrisoft® product after a wound has been cleaned.

1 shows the cross-section of a CT image of a composite material 1 according to the invention, which has a foam layer 2 and a fiber layer 3 arranged thereon. Foam layer 2 and fiber layer 3 are connected to one another by needling, so that fibers of fiber layer 3 are in foam layer 2 have penetrated and form capillary channels 4 in this. It can be seen that the capillary channels 4 extend from the fiber layer 3 into the foam layer 2.

Fig. 2 shows the cross section of a light microscopy image of a

Composite material 1 according to the invention after a wound cleaning with the foam side. In the figure, the interface between foam layer 2 and fiber layer 3 is illustrated as border line 5. One can clearly see how wound components are absorbed deep into the foam layer 2 and exceed the boundary line 5, that is to say have penetrated 3 into the fiber layer.

3 shows the cross section of a scanning electron microscope image of a cotton gauze after a wound has been cleaned. You can clearly see how that

Wound components are only retained on the surface of the cotton gauze (area within dot-dash line).

4 shows the cross section of a scanning electron microscope image of a wound cleansing material according to the invention after a wound cleansing. It can be clearly seen how wound exudate is guided from the foam layer into the fiber layer along the capillary channels formed by the fibers (marked within the dotted line).

FIG. 5 shows the defined movement of a wiping cycle for cleaning a test wound on pig skin. The wound surface 6 is cleaned with low pressure (to simulate gentle cleaning) and in a defined horizontal 7 and vertical 8 movement that results in a wiping cycle 9.

6 shows the cross section of a scanning electron microscope image of the Debrisoft® product after a wound has been cleaned. You can clearly see how that Wound components are only retained on the surface (area within oval).

Examples

Example 1: Production of a foam layer

A water phase is produced for foam production by dissolving / dispersing the surfactant Pluronic F87 in a concentration of 0.5% by weight. At the same time, a Teflon mold with a depth sufficient to produce a foam 7 mm thick is lined with casting paper. The

Prepolymer Hypol 2001 is added to the water phase at a concentration of 40% by weight and mixed at room temperature with a dispersion disk (1600 rpm). The resulting mixture is immediately poured into the mold. It is foamed against air and cured for 10 minutes. The casting paper is then removed and dried at a temperature of 150 ° C. for 3 hours.

Example 2: Production of a thermally bonded fiber layer

To produce the thermally solidified fiber layer, staple fibers are used: 70% by weight polyester fibers (Grisuten® from Märkische Faser GmbH) with a fiber titer of 1.7 dtex and a fiber length of 60 mm and 30% by weight of a polyethylene terephthalate / polyethylene core - Sheath binding fiber (Trevira® 256 from Trevira GmbH) with a fiber titer of 3 dtex and a fiber length of 50 mm. These staple fibers are placed in a fiber layer by means of a card according to methods known to those skilled in the art. The

The weight per unit area of the fiber layer is 150 g / m ² . Then the

The fiber layer is thermally bonded in a hot air oven at 150 ° C and a speed of 2 m / min. Example 3: Production of a wound cleansing article by mechanical needling of the fiber layer and foam layer

To produce the wound cleansing article according to the invention, an open-pored foam layer from Example 1 and a thermally solidified one are used

Fiber layer from Example 2 provided. In a needle process, the

Fleece layer with a puncture density of 100 / cm ² and puncture depth of 10 mm needled against the foam layer. The surface of the fleece layer that was turned away from the belt side in the oven is located on which the

Foam layer surface facing away from the surface. The foam layer and fiber layer are connected to one another by the needling process. In this way, both a mechanically stable bond and a slightly fibrous surface are created on the foam. In addition, the fibers of the fiber layer penetrate the foam layer, form capillary channels in the foam layer and protrude at least partially from the side of the foam layer facing away from the fiber layer. The composite material obtained has a higher abrasiveness on the foam layer than on the fiber layer. Through the from the

Foam layer with outstanding fibers, the foam layer has a more pleasant feel than the pure foam layer. To make a

The composite material is made up of wound cleansing articles. There is no significant loss of fibers.

Example 4: Determination of the mechanical stability of the

Composite material from example 3

The mechanical stability is measured as the tensile strength of the composite material according to the invention with the aid of a tensile test according to EN 29073-03

(Deviations: no conditioning and withdrawal speed 200 mm / min) tested in the longitudinal direction with a specimen size of 300 x 50 mm. The dry and wet tensile strength was determined as

Wound cleansing materials are usually applied moist. To To assess the wet tensile strength, the test specimens were placed in tap water for about 30 minutes and then gently squeezed out and left hanging to drain for 5 - 10 minutes. Table 1 shows a comparison of the maximum tensile strength and maximum tensile strength elongation for an open-cell foam, the composite material according to the invention and the standard cotton gauze. The composite material according to the invention has a significantly higher maximum tensile strength in the wet and in the dry state compared to a pure open-cell foam. As the fiber layer penetrates the foam layer, the foam layer is mechanically reinforced and the tensile strength increased. When dry, this achieves the strength of a standard cotton compress. In the wet state, the composite material according to the invention has a lower but sufficient maximum tensile strength than the standard cotton gauze. The maximum tensile force elongation, however, is significantly higher than that of cotton gauze. As a result, the composite material according to the invention is ideally suited for moist

Wound cleaning, as the high elasticity can prevent tearing during cleaning. Furthermore, the increased elongation offers the advantage that the composite material can adapt better to the wound bed.

Table 1: Comparison of mean maximum tensile strength and maximum tensile strength elongation for open-cell foam, a composite material according to the invention and standard cotton gauze

Dry wet

Maximum tensile force maximum tensile force maximum tensile force maximum tensile force

Stretching stretching

[N] [%] [N] [%]

Open line

Foam layer 22.1 165.8 10.2 58.9

[2.5 mm]

According to the invention

Composite 87.4 135.3 76.0 130.3

[~ 4 mm]

default

Cotton gauze 83.3 5.0 143.7 8.2

[<1 mm]

Example 5: Determination of the cleaning performance of the

Wound cleansing article in an ex vivo wound model

The composite material produced in Example 3 was made into a wound cleansing article according to the invention by punching to a size of 10 cm × 10 cm. The cleaning performance of the invention

Wound cleansing articles were based on an ex vivo wound model

Pig skin rated. The wound to be cleaned was prepared as follows: First, the pig skin was fixed with the inside of the skin facing up in a frame (area for wound 10 cm x 10 cm) and scored with a scalpel in the form of a grid pattern. The skin was then lightly burned with a flambeer burner (20 seconds, medium flame, distance approx. 20 cm), so that an uneven wound bed caused by the gaping of the cuts

arises. Escaping grease was carefully removed by dabbing with a paper towel. Then 4 ml protein solution (100 g / L protein powder

(e.g. Body & Fit Egg White Powder in phosphate-buffered saline solution (8.0 g / L sodium chloride (NaCI), 0.2 g / L potassium chloride (KCl), 1.42 g / L Disodium hydrogen phosphate (Na2FIP04) or 1.78 g / L

Disodium hydrogen phosphate dihydrate (Na2HP04 * 2 H20), 0.27 g / L

Potassium dihydrogen phosphate (KH2P04)) applied and baked in again with the help of a flame beer burner (30 seconds, medium flame, distance approx. 20 cm). The protein solution is suitable for simulating fibrin coatings in the wound. In a final step, 2 g of artificial exudate solution (5% Blanose, 40 g / L protein powder, 1 g / L sugar, artificial blood (150 drops to 300 mL, 2g / L sunflower oil, 3.7 g / L sodium carbonate, 3rd g / L quartz sand, all dissolved in PBS), applied to the wound using a wooden spatula and burned in again until a black crust (30 seconds, medium flame, distance approx. 20 cm) is formed. The simulated wound is treated for 2 hours at Let it rest at room temperature so that previously applied exudate cannot be easily removed again.

For cleaning, the wound cleaning article was moistened with 5 sprays of water on the foam side (10 cm × 10 cm) and placed on the wound for one minute with the foam side facing the wound surface. The wound surface was then cleaned with low pressure (to simulate gentle cleaning) and in a defined horizontal and vertical movement that resulted in a wiping cycle (see FIG. 5). The cleaning takes place for 3 minutes with 11 wiping cycles.

The cleaning performance was evaluated using image analysis of the

burned (black) areas before and after wound cleaning. The prepared pig skins were recorded with a single lens reflex camera (Canon D70) with a fixed focal length lens (60 mm) using a copy stand. Care was taken to ensure that the lighting and the distance (resulting magnification) between the object and the lens were the same for all images. In the course of the investigation, a

Metal frame applied to smooth the pork skins. Over a Threshold setting and a 15 x 15 pixel median filter were used to identify the black areas in the image and highlight them in green. An upper limit of 80 was chosen for all images in the flistogram. This, and the consistent exposure setup, ensure that the results of all samples are comparable. The last step was to limit the area of the image that could be sensibly evaluated (ROI). Due to the calibration of the images during the recording, it was then possible to specify the marked areas as area proportions in pm. Table 2: Comparison of the cleaning performance of cotton gauze, Debrisoft® and a wound cleaning article according to the invention

Surface before surface after cleaning performance Cleaning Cleaning in

[mm ² ] [mm ² ] [%]

Cotton gauze 629.0 286.0 54 ^~ 5

Cotton gauze 1491, 0 1010.0 32.3

Debrisoft® 3162.0 1276.0 59.6

Debrisoft® 3374.0 1289.0 61.7

According to the invention

Wound cleansing articles 2924.0 922.0 68.5

According to the invention

Wound cleansing articles 59.0 14.0 76.3

Example 6 Determination of the absorption of wound components by the wound cleaning article according to the invention from Example 5

To determine the absorption of wound components in the

Wound cleansing articles were taken with light and scanning electron microscopy. It can be clearly seen (FIG. 2) that a transport of wound components beyond the border of the foam layer into the fiber layer takes place. In contrast, absorption in cotton gauze (FIG. 3 area within dash-dot oval) and Debrisoft (FIG. 6 area within oval) takes place only on the surface or in the upper part of the structure. It can also be seen (dashed area in FIG. 3) that the capillary channels allow cross-layer transport and containment of exudate throughout

Enable wound cleansing articles.

The wound cleansing article of the present invention is used in terms of its absorbency compared to cotton gauze and the product

Debrisoft® tested according to BS EN 13726-1: 2002. It was found that it shows an increased absorption of the aqueous test solution in comparison to standard cotton gauze and to the product Debrisoft® (cf. Table 3). Flieran is advantageous that more wound components and liquids such as irrigation solutions used to support wound cleaning and / or

Wound exudate can be absorbed within a wound cleansing application.

Table 3: Comparison of the absorption of cotton gauze, Debrisoft® and a wound cleaning article according to the invention

absorption

[g / g]

Cotton gauze 5.2

Debrisoft® 5.9

Claims

1. Wound cleansing article comprising a composite material (1) which has a foam layer (2) and a fiber layer (3) arranged on and in the foam layer (2), characterized in that the fiber layer (3) is at least partially thermally solidified and the Foam layer (2) and fiber layer (3) are connected to one another by needling, with fibers of the fiber layer (3) penetrating the foam layer (2) and forming capillary channels (4) which would extend from the fiber layer (3) into the foam (2) extend.

2. Wound cleansing article according to claim 1, characterized in that the fibers of the fiber layer (3) penetrate the foam layer (2) and at least partially protrude from the side of the foam layer (2) facing away from the fiber layer (3).

3. wound cleaning article according to claim 1 or 2, characterized

characterized in that the fiber layer (3) comprises synthetic fibers.

4. wound cleaning article according to one or more of the preceding claims, characterized in that the fiber layer (3)

Has matrix fibers and a binder, in particular binder fibers.

5. Wound cleansing article according to one or more of the preceding claims, characterized in that the fiber layer (3) has hydrophobic fibers, in particular polyester and / or polyolefin fibers.

6. Wound cleaning article according to one or more of the preceding claims, characterized in that the fibers contained in the fiber layer (3), in particular the matrix fibers and / or the Binding fibers are staple fibers, preferably with a staple length between 20 mm and 150 mm.

7. Wound cleansing article according to one or more of the preceding claims, characterized in that the foam (2) is a hydrophilic polymer foam, in a proportion of more than 50 wt .-%, more preferably more than 70 wt .-%, in particular more than 90% by weight based on the polymer content of the foam layer (2).

8. Wound cleansing article according to one or more of the preceding claims, characterized in that the foam layer (2) is open-line.

9. Wound cleansing article according to one or more of the preceding claims, characterized in that the foam layer (2) has at least one open-line surface.

10. Wound cleaning article according to one or more of the preceding claims, characterized by a maximum tensile force / elongation measured according to EN 29073-03 (wet) of more than 40%.

11. Wound cleansing article according to one or more of the preceding claims, characterized in that the composite material (1) has a hydrophilic foam layer (2) in combination with a hydrophobic fiber layer (3).

12. Wound cleaning article according to claim 11, characterized in that hydrophobic fibers of the fiber layer (3) penetrate the hydrophilic foam layer (2) and at least partially protrude from the side of the foam layer (2) facing away from the fiber layer (3).

13. Wound cleansing article according to one or more of the preceding claims, characterized in that it is sterile.

14. A method for producing one according to the invention

Wound cleansing article comprising the following steps:

A arranging an at least partially thermally solidified

Fiber layer (3) on a foam layer (2);

B needling of foam layer (2) and fiber layer (3) in such a way that a composite material (1) is formed in which fibers of the fiber layer (3) have penetrated into the foam layer (2) and form capillary channels (4) which extend from the fiber layer (3) extend into the foam layer (2).

15. A method for producing one according to the invention

Wound cleansing article comprising the following steps:

A arranging a fiber layer (3) on a foam layer (2);

C Thermal consolidation of the composite material (1).